Mine has oval holes in the rear door and 2 bolt holes on the instrument panel. I also found this web site http://www.equipmentwatch.com and when I enter my serial number it says its a 1994 production year which sounds about right.The serial number is the only way to check for the year built. I would think the dealers in your area have some kind of book on equipment listing the serial numbers and the year of production.
A more general way to tell year of production is to look at the rear door. The first few years the door had stamped oval openings. In 98 I think or 99 they went to a slat style rear door. Also the threashold up front was metal until I believe 1999 when they went to plastic.
You can not go by the instrument panel since many of the gray boards were replaced with gold trimmed boards. I think in 1999 they went to an instrument panel with four retaining bolts instead of two.